1. Field of the Invention
The invention relates generally to machinery such as that used to fabricate cans such as beverage cans and the like, and more specifically to a trimmer arrangement that is used to trim off portions of the cans during their manufacture, and which is quickly adjustable in a manner which reduces the amount of down time during a change in can diameter.
2. Brief Description of the Related Art
A known trimmer arrangement operates by driving a circular knife along the inside wall of the can. In a known can fabrication line, the cans are trimmed using a plurality of trimmer arrangements which are mounted on a rotatable base. An example of such a trimming arrangement can be found in U.S. Pat. No. 4,181,050 issued on Jan. 1, 1980 in the name of Stroobants et al. The content of this patent is hereby incorporated by reference into this application.
In this latter mentioned arrangement, the cans are fed to the trimming arrangement and trimmed while orbiting along a circular path about the axis of rotation of the rotatable base. While this arrangement is efficient in that cans are continuously fed to the continuously rotatable base member and trimmed without interruption as they orbit the axis, a problem is encountered in that for larger cans the radial distance between the can centerline and the knife diameter is greater than with a smaller diameter can. Changes in can diameter therefore require a mechanical adjustment and/or replacement of parts to reposition the trim cartridge/knife diameter relative to the fixed can centerline. The can centerline that includes the cut zone is constant for the full range of can diameters the trimmer is designed to run. The speed of the circular knives which are used also need to be adjusted with the change in can diameter. This can require the replacement of gears in a gear train which supplies rotational energy from a motor or the like.
With the above mentioned trimming arrangement this change over from a set-up suited for one diameter can to a set-up suitable for a can having a different diameter requires a considerable amount of work and an undesirably long downtime.